Solenoids typically require a relatively large current to energize and a lesser or smaller current to stay closed after being energized. Well-known circuits used to drive solenoids include a half-bridge peak-and-hold driver. Some such circuits modulate the width or time duration of current pulses provided to a solenoid in order to energize the solenoid, i.e., provide a actuation current, and hold it closed, i.e., provide a holding current.
A problem with prior art half-bridge peak and hold drivers is their inability to detect short circuits to the battery voltage or to ground or the driver is on. More particularly, the high side of a solenoid coil is inadvertently connected to the battery voltage directly, which is also known as a short-circuit-to-battery fault, the solenoid as well as electronics that drive it can be damaged. Similarly, when the low side of the coil is short circuited to ground, the solenoid and electronics that drive it can also be damaged. An apparatus and method for detecting short circuits of the high side and low side of an inductive load, such as a solenoid, driven by a half-bridge peak and hold driver, would be an improvement over the prior art.